The US State Department has barred 16 Saudi officials from entering the US for their role in the murder of prominent journalist Jamal Khashoggi, a permanent US resident and critic of the Saudi government.

On Monday, Secretary of State Mike Pompeo announced that 16 Saudi individuals, including one of the closest aides to Crown Prince Mohamed Bin Salman, were barred from entry into the country.

“In cases where the Secretary of State has credible information that officials of foreign governments have been involved in significant corruption or gross violations of human rights,” a statement by the state department read, “those individuals and their immediate family members are ineligible for entry into the United States.”

The announcement comes as President Donald Trump faces pressure from Congress to adopt a harsher response to the Khashoggi killing.

Khashoggi, a Washington Post and Middle East Eye columnist, was killed and dismembered on 2 October in the Saudi consulate in Istanbul by a team of 15 agents sent from Riyadh. His body has never been recovered.

A little over a month after the murder, the CIA concluded that bin Salman was behind Khashoggi's murder. Bin Salman has denied any knowledge of the killing or its botched cover-up, which Riyadh has described as a "rogue operation".

The barring of the officials follows another designation by the Department of the Treasury in November when 17 individuals were sanctioned for their role in the Khashoggi murder under the Global Magnitsky Human Rights Accountability Act. Their assets were frozen in the US and US citizens were prohibited from entering into transactions with them.

All of the individuals sanctioned last year are on the list that was announced on Monday except Mohammad Alotaibi, who was the Saudi consul general to Istanbul. He led early efforts by Saudi Arabia to convince journalists and critics that Khashoggi had left the consulate alive on 2 October.

Four days after the murder, Alotaibi, who is believed to have personally witnessed the crime, invited Reuters journalists into the consulate to show them that Khashoggi was not there.

It is unclear why he has been removed from the list.

Former Saudi consul in Istanbul Mohammad Alotaibi is not among those sanctioned on Monday (Reuters)

After having first denied that the murder occurred, Saudi Arabia said the operation was carried out by agents who were out of control. A trial of 11 suspects opened earlier this year in Saudi Arabia.

Saud al-Qahtani, a top aide to Bin Salman who was fired after the murder and is believed to have planned the Istanbul operation, is not among the 11 suspects, according to sources familiar with the matter. Qahtani is, however, among those who have been sanctioned by the US Treasury and barred from entering the country.

Last October, a Saudi source with intimate knowledge of his country's intelligence services told Middle East Eye about a death squad that operated under the guidance and supervision of Mohammad bin Salman, the powerful Saudi crown prince and de facto ruler.

The Firqat el-Nemr, or 'Tiger Squad', is well known to the US intelligence services. It was formed more than a year ago and is comprised of 50 of the best-skilled intelligence and military operatives in the kingdom.